Take a low voltage supply on the order of 12 volts or so and tie it to
the shunt through a couple hundred ohms, measure the current draw through
and voltage drop across the shunt and apply ohm's law. Make sure the
shunt
is disconnected from the rest of the metering circuit.
I usually double the required shunt value and use a adjustable series
pot (10 turn)
between the shunt and the meter ( a series multiplier) then the pot can
be used to
calibrate the meter. The higher effective "R" across the meter movement
also allows
for faster meter action.
Mark WB8JKR
On Thu, 17 Jun 1999 20:47:35 -0700 zeitler@ibm.net writes:
>
>Gents,
>Is there a simple way to accurately measure the low resistance of a
>current
>meter shunt? I am trying to get my plate current and grid current
>meters
>calibrated and I need to verify the values of the shunt R but the Ip
>shunt
>is less than .3 ohms and the Ig shunt is less than 1.6 ohms. My Fluke
>77BN
>is of no real help at these low values.
>
>Lane Zeitler
>Ku7i
>
>
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